薬物の血清蛋白結合の主役を果たすヒト血清アルブミン(HSA)分子には，この二十有余年にわたる私共の研究を含めた蛍光プローブ法や化学修飾法による検討，さらにはHeやCarterらによるX線構造解析の結果から，サイトI，サイトII及びサイトIIIと呼ばれる三つの薬物結合サイトの存在が明らかにされてきました。このような血清蛋白分子上の薬物結合サイトの同定が，薬物相互作用の予測に役立つことは言うまでもないことです。
　しかしながら，実際の薬物投与における薬物間の相互作用を考えたとき，その実態は複雑なように思われます。なぜなら，病態における薬物の蛋白結合は内因性物質の蓄積による競合置換に加えて，翻訳後修飾あるいはpH変化や内因性物質の結合による血清蛋白質の立体構造変化に伴うアロステリックな置換現象が惹起される可能性が予測されるからです。
　現在，私共は各種スペクトル法などの従来の方法に加え，分子生物学的手法などを駆使して，薬物の血清蛋白結合の機序解明を行うとともに，薬物間の相互作用を予測し，合理的で安全かつ有効な処方設計の立案ができるように，薬物の蛋白結合について総合的な評価を行っております。

　具体的には以下のトピックスについて研究しております。

1．生体内HSAの疾患時における構造及び機能変化に関する研究

2．HSA変異体及びpolymeric-HSAを利用したドラッグデリバリーシステムに関する研究

3．HSA部位変異法によるHSA分子上の薬物結合部位のトポロジー解析

研究業績（２０００〜２００９）

２００９

Taguchi K, Maruyama T, Iwao Y, Sakai H, Kobayashi K, Horinouchi H, Tsuchida E, Kai T, Otagiri M, Pharmacokinetics of single and repeated injection of hemoglobin-vesicles in hemorrhagic shock rat model. J Control Release, in press (2009).

Iwao Y, Hiraike M, Kragh-Hansen U, Kawai K, Suenaga A, Maruyama T, Otagiri M. Altered chain-length and glycosylation modify the pharmacokinetics of human serum albumin. Biochim Biophys Acta. 1794, 634-641 (2009)

Anraku M, Fujii T, Furutani N, Kadowaki D, Maruyama T, Otagiri M, Gebicki JM, Tomida H. Antioxidant effects of a dietary supplement: Reduction of indices of oxidative stress in normal subjects by water-soluble chitosan. Food Chem Toxicol. 47, 104-109 (2009)

２００８

Ishima Y, Akaike T, Kragh-Hansen U, Hiroyama S, Sawa T, Suenaga A, Maruyama T, Kai T, Otagiri M. S-Nitrosylated Human Serum Albumin-mediated Cytoprotective Activity Is Enhanced by Fatty Acid Binding. J Biol Chem. 283, 34966-34975 (2008)

Kitamura R, Matsuoka K, Nagayama S, Otagiri M. Time-dependent induction of rat hepatic CYP1A1 and CYP1A2 expression after single-dose administration of the anti-angiogenic agent TSU-68. Drug Metab Pharmacokinet. 23, 421-427 (2008)

Iwao Y, Nakajou K, Nagai R, Kitamura K, Anraku M, Maruyama T, Otagiri M. CD36 is one of important receptors promoting renal tubular injury by advanced oxidation protein products. Am J Physiol Renal Physiol. 295, 1871-1880. (2008)

Anraku M, Kitamura K, Shintomo R, Takeuchi K, Ikeda H, Nagano J, Ko T, Mera K, Tomita K, Otagiri M. Effect of intravenous iron administration frequency on AOPP and inflammatory biomarkers in chronic hemodialysis patients: a pilot study. Clin Biochem. 41, 1168-1174. (2008)

Anraku M, Kabashima M, Namura H, Maruyama T, Otagiri M, Gebicki JM, Furutani N, Tomida H. Antioxidant protection of human serum albumin by chitosan. Int J Biol Macromol. 43, 159-164 (2008)

Mera K, Nagai M, Brock JW, Fujiwara Y, Murata T, Maruyama T, Baynes JW, Otagiri M, Nagai R. Glutaraldehyde is an effective cross-linker for production of antibodies against advanced glycation end-products.J Immunol Methods. 334, 82-90 (2008)

Kitamura R, Asanoma H, Nagayama S, Otagiri M. Identification of human liver cytochrome P450 isoforms involved in autoinduced metabolism of the anti-angiogenic agent TSU-68 ((Z)-5-[(1,2-dihydro-2-oxo-3H-indol-3-ylidene)methyl]-2,4-dimethyl-1H-pyrrole-3-propanoic acid). Drug Metab Dispos. 36, 1003-1009 (2008)

Katayama N, Nakajou K, Komori H, Uchida K, Yokoe J, Yasui N, Yamamoto H, Kai T, Sato M, Nakagawa T, Takeya M, Maruyama T, Otagiri M. Design and evaluation of S-nitrosylated human serum albumin as a novel anticancer drug. J. Pharmacol. Exp. Ther., 325, 69-76, (2008)

Inoue K, Nakai Y, Ueda S, Kamigaso S, Ohta KY, Hatakeyama M, Hayashi Y, Otagiri M, Yuasa H. Functional characterization of PCFT/HCP1 as the molecular entity of the carrier-mediated intestinal folate transport system in the rat model. Am. J. Physiol. Gastrointest. Liver. Physiol., 294, 660-668, (2008)

２００７

Anraku, M., Kouno, Y., Kai, T., Tsurusaki, Y., Yamasaki, K., and Otagiri, M. The role of N-acetyl-methioninate as a new stabilizer for albumin products. Int. J. Pharm,. 329, 19-24, (2007)

Chuang, V. T., and Otagiri, M. Recombinant human serum albumin. Drugs Today (Barc), 43, 547-561, (2007)

Ishima, Y., Akaike, T., Kragh-Hansen, U., Hiroyama, S., Sawa, T., Maruyama, T., Kai, T., and Otagiri, M. Effects of endogenous ligands on the biological role of human serum albumin in S-nitrosylation. Biochem. Biophys. Res. Commun., 364, 790-795, (2007)

Ishima Y, Sawa T, Kragh-Hansen U, Miyamoto Y, Matsushita S, Akaike T, Otagiri M. S-Nitrosylation of human variant albumin Liprizzi (R410C) confers potent antibacterial and cytoprotective properties. J Pharmacol Exp Ther. 320:969-977 (2007)

Anraku M, Kouno Y, Kai T, Tsurusaki Y, Yamasaki K, Otagiri M. The role of N-acetyl-methioninate as a new stabilizer for albumin products. Int J Pharm. 329:19-24 (2007)

Mera K, Nagai R, Haraguchi N, Fujiwara Y, Araki T, Sakata N, Otagiri M. Hypochlorous acid generates N epsilon-(carboxymethyl)lysine from Amadori products. Free Radic Res. 41:713-718 (2007)

２００６

Kragh-Hansen U, Watanabe H, Nakajou K, Iwao Y, Otagiri M. Chain length-dependent binding of fatty acid anions to human serum albumin studied by site-directed mutagenesis. J Mol Biol. 363:702-712 (2006)

Matsushita S, Chuang VT, Kanazawa M, Tanase S, Kawai K, Maruyama T, Suenaga A, Otagiri M. Recombinant human serum albumin dimer has high blood circulation activity and low vascular permeability in comparison with native human serum albumin. Pharm Res.23:882-891 (2006)

Chuang VT, Otagiri M. Stereoselective binding of human serum albumin. Chirality.18:159-166 (2006)

Iwao Y, Anraku M, Hiraike M, Kawai K, Nakajou K, Kai T, Suenaga A, Otagiri M. The structural and pharmacokinetic properties of oxidized human serum albumin, advanced oxidation protein products (AOPP). Drug Metab Pharmacokinet. 21:140-146 (2006)

Iwao Y, Anraku M, Yamasaki K, Kragh-Hansen U, Kawai K, Maruyama T, Otagiri M. Oxidation of Arg-410 promotes the elimination of human serum albumin. Biochim Biophys Acta. 1764:743-739 (2006)

２００５

Mera K, Anraku M, Kitamura K, Nakajou K, Maruyama T, Tomita K, Otagiri M. Oxidation and carboxy methyl lysine-modification of albumin: possible involvement in the progression of oxidative stress in hemodialysis patients. Hypertens Res. 28:973-980 (2005)

Otagiri M. A molecular functional study on the interactions of drugs with plasma proteins. Drug Metab Pharmacokinet. 20:309-323 (2005) Review.

Ma SF, Anraku M, Iwao Y, Yamasaki K, Kragh-Hansen U, Yamaotsu N, Hirono S, Ikeda T, Otagiri M. Hydrolysis of angiotensin II receptor blocker prodrug olmesartan medoxomil by human serum albumin and identification of its catalytic active sites. Drug Metab Dispos. 33:1911-1919 (2005).

Ghuman J, Zunszain PA, Petitpas I, Bhattacharya AA, Otagiri M, Curry S. Structural basis of the drug-binding specificity of human serum albumin. J Mol Biol. 353:38-52 (2005).

Mera K, Anraku M, Kitamura K, Nakajou K, Maruyama T, Otagiri M. The structure and function of oxidized albumin in hemodialysis patients: Its role in elevated oxidative stress via neutrophil burst. Biochem Biophys Res Commun. 334:1322-1328 (2005).

Nakajou K, Horiuchi S, Sakai M, Hirata K, Tanaka M, Takeya M, Kai T, Otagiri M. CD36 Is not involved in scavenger receptor-mediated endocytic uptake of glycolaldehyde- and methylglyoxal-modified proteins by liver endothelial cells. J. Biochem. 137:607-616 (2005).

Kawasaki CI, Nishi R, Uekihara S, Hayano S, Kragh-Hansen U, Otagiri M. How tightly can a drug be bound to a protein and still be removable by charcoal hemoperfusion in overdose cases? Clin Toxicol. 43:95-99 (2005).

Nakajou K, Horiuchi S, Sakai M, Haraguchi N, Tanaka M, Takeya M, Otagiri M. Renal clearance of glycolaldehyde- and methylglyoxal-modified proteins in mice is mediated by mesangial cells through a class A scavenger receptor (SR-A). Diabetologia 48:317-327 (2005).

Takamura N, Maruyama T, Chosa E, Kawai K, Tsutsumi Y, Uryu Y, Yamasaki K, Deguchi T, Otagiri M. Bucolome, a potent binding inhibitor for furosemide, alters the pharmacokinetics and diuretic effect of furosemide: potential for use of bucolome to restore diuretic response in nephrotic syndrome. Drug Metab. Dispos. 33:596-602 (2005).

Kragh-Hansen U, Saito S, Nishi K, Anraku M, Otagiri M. Effect of genetic variation on the thermal stability of human serum albumin.
Biochim. Biophys. Acta 1747:81-88 (2005).

Fukuzawa K, Saitoh Y, Akai K, Kogure K, Ueno S, Tokumura A, Otagiri M, Shibata A. Antioxidant effect of bovine serum albumin on membrane lipid peroxidation induced by iron chelate and superoxide. Biochim. Biophys. Acta 1668:145-155 (2005).

２００４

Komatsu T, Oguro Y, Teramura Y, Takeoka S, Okai J, Anraku M, Otagiri M, Tsuchida E. Physicochemical characterization of cross-linked human serum albumin dimer and its synthetic heme hybrid as an oxygen carrier. Biochim. Biophys. Acta. 1675:21-31 (2004).

Harada D, Anraku M, Fukuda H, Naito S, Harada K, Suenaga A, Otagiri M. Kinetic studies of covalent binding between N-acetyl-L-cysteine and human serum albumin through a mixed-disulfide using an N-methylpyridinium polymer-based column. Drug Metab. Pharmacokinet.19:297-302 (2004).

Yamasaki K, Maruyama T, Takadate A, Suenaga A, Kragh-Hansen U, Otagiri M. Characterization of site I of human serum albumin using spectroscopic analyses: Locational relations between regions Ib and Ic of site I. J Pharm. Sci. 93:3004-3012 (2004).

Anraku M, Tsurusaki Y, Watanabe H, Maruyama T, Kragh-Hansen U, Otagiri M. Stabilizing mechanisms in commercial albumin preparations: octanoate and N-acetyl-l-tryptophanate protect human serum albumin against heat and oxidative stress. Biochim. Biophys. Acta 1702:9-17 (2004).

Matsushita S, Isima Y, Chuang VT, Watanabe H, Tanase S, Maruyama T, Otagiri M. Functional analysis of recombinant human serum albumin domains for pharmaceutical applications. Pharm. Res. 21:1926-1934 (2004).

Anraku M, Kitamura K, Shinohara A, Adachi M, Suenaga A, Maruyama T, Miyanaka K, Miyoshi T, Shiraishi N, Nonoguchi H, Otagiri M, Tomita K. Intravenous iron administration induces oxidation of serum albumin in hemodialysis patients. Kidney Int. 66: 841-848, (2004).

Sakurai Y, Ma SF, Watanabe H, Yamaotsu N, Hirono S, Kurono Y, Kragh-Hansen U, Otagiri M. Esterase-like activity of serum albumin: characterization of its structural chemistry using p-nitrophenyl esters as substrates. Pharm. Res. 21: 285-292 (2004).

２００３

Nakajou K, Watanabe H, Kragh-Hansen U, Maruyama T, Otagiri M. The effect of glycation on the structure, function and biological fate of human serum albumin as revealed by recombinant mutants. Biochim. Biophys. Acta 1623: 88-97 (2003).

Anraku M, Kragh-Hansen U, Kawai K, Maruyama T, Yamasaki Y, Takakura Y, Otagiri M. Validation of the chloramine-T induced oxidation of human serum albumin as a model for oxidative damage in vivo. Pharm. Res. 20: 684-692 (2003).

２００２

Harada D, Naito S, Otagiri M. Kinetic analysis of covalent binding between N-acetyl-L-cysteine and albumin through the formation of mixed disulfides in human and rat serum in vitro. Pharm. Res. 19: 1648-1654 (2002).

Chuang VT, Otagiri M. How do fatty acids cause allosteric binding of drugs to human serum albumin? Pharm. Res. 19:1458-1464 (2002).

Kragh-Hansen U, Chuang VT, Otagiri M. Practical aspects of the ligand-binding and enzymatic properties of human serum albumin. Biol. Pharm. Bull. 25: 695-704. Review (2002).

Chuang VT, Kragh-Hansen U, Otagiri M. Pharmaceutical strategies utilizing recombinant human serum albumin. Pharm. Res. 19: 569-577. Review (2002).

Harada D, Naito S, Hiraoka I, Otagiri M. In vivo kinetic analysis of covalent binding between N-acetyl-L-cysteine and plasma protein through the formation of mixed disulfide in rats. Pharm. Res. 19:615-620 (2002).

Watanabe H, Yamasaki K, Kragh-Hansen U, Tanase S, Harada K, Suenaga A, Otagiri M. In vitro and in vivo properties of recombinant human serum albumin from Pichia pastoris purified by a method of short processing time. Pharm. Res. 18: 1775-1781 (2002).

２００１

Anraku M, Yamasaki K, Maruyama T, Kragh-Hansen U, Otagiri M. Effect of oxidative stress on the structure and function of human serum albumin. Pharm. Res. 18:632-639 (2001).

Harada D, Naito S, Kawauchi Y, Ishikawa K, Koshitani O, Hiraoka I, Otagiri M. Determination of reduced, protein-unbound, and total concentrations of N-acetyl-L-cysteine and L-cysteine in rat plasma by postcolumn ligand substitution high-performance liquid chromatography. Anal. Biochem. 290:251-259 (2001).

Sakai T, Yamasaki K, Sako T, Kragh-Hansen U, Suenaga A, Otagiri M. Interaction mechanism between indoxyl sulfate, a typical uremic toxin bound to site II, and ligands bound to site I of human serum albumin. Pharm. Res. 18: 520-524 (2001).

Watanabe H, Kragh-Hansen U, Tanase S, Nakajou K, Mitarai M, Iwao Y, Maruyama T, Otagiri M. Conformational stability and warfarin-binding properties of human serum albumin studied by recombinant mutants. Biochem. J. 357: 269-274 (2001).

Chuang VT, Otagiri M. Flunitrazepam, a 7-nitro-1,4-benzodiazepine that is unable to bind to the indole-benzodiazepine site of human serum albumin. Biochim. Biophys. Acta 1546: 337-345 (2001).

Watanabe H, Tanase S, Nakajou K, Maruyama T, Kragh-Hansen U, Otagiri M.Role of arg-410 and tyr-411 in human serum albumin for ligand binding and esterase-like activity. Biochem. J. 349: 813-819 (2001).

２０００

Yamasaki K, Rahman MH, Tsutsumi Y, Maruyama T, Ahmed S, Kragh-Hansen U, Otagiri M. Circular dichroism simulation shows a site-II-to-site-I displacement of human serum albumin-bound diclofenac by ibuprofen. AAPS. Pharm. Sci. Tech. 14: E12 (2000).

Kawasaki C, Nishi R, Uekihara S, Hayano S, Otagiri M. Charcoal hemoperfusion in the treatment of phenytoin overdose. Am. J. Kidney. Dis. 35:323-326 (2000).

日本語総説

安楽　誠, 丸山　徹, 小田切優樹. 構造特性からみたアルブミンー薬物結合サイトと治療設計. 臨床検査 48:521-527 (2004).

丸山　徹, 小田切優樹. 血清アルブミンのドラッグデリバリーシステムへの応用. 人工血液 9:88-94 (2004).

渡邊博志, 丸山　徹, 小田切優樹. ヒト血清アルブミン分子上の薬物結合部位のトポロジー解析. 薬物動態 16:264-270 (2001).

川崎知世, 小田切優樹. 蛋白結合率を指標とした薬物中毒時の活性炭血液吸着法の効果とその予測. 薬物動態 15:275-280 (2000).